The potential of rail as an environmental solution: Setting the agenda

Rail is often advanced as an environmentally superior alternative to road transportation. A market segmentation analysis shows rail has a relative advantage in regular long distance trips to high density nodes. Yet, such trips are a limited and shrinking share of the total transport market. Rail's direct environmental benefits as a substitute for the car may thus be limited in time and space. Rail may have some indirect environmental benefits through its effects on metropolitan structure within comprehensive transport and land use programs. An analysis of these issues raises several unanswered questions, which are suggested as a research agenda to evaluate rail's long term potential as an environmental solution.